Cooling tests

Fig. 9. Stored energy release curves for CSF graphite irradiated at 30°C in the Hanford K reactor cooled test hole [64], Note, the rate (with temperature) of stored energy release (J/Kg-K) exceeds the specific heat and thus under adiabatic conditions self sustained heating will occur.

Such a second energy level can be applied to either a heating or cooling GRT. However, it is also possible to combine heating and cooling tests in one test and at the same time use different energy levels (Figure 55). 

Assemble an apparatus as shown in Fig. 99a. Put 10 g of purified dry phosphorus into test tube 1. Cool test tube 2 with ice. Displace the air from the apparatus with a stream of dry nitrogen (carbon dioxide). Pass a stream of dry chlorine through the apparatus, heating tube 1 in a sand bath up to a temperature of 250-300 °C (use a thermometer ). Carry out chlorination so that the formed phosphorus... 

Seal off offtake 2 and spill metallic zirconium into section 5 via offtake 6. Tightly close offtake 6 with a rubber stopper. Connect the apparatus via offtake 8 to a vacuum system for 15-20 min. Next place test tube 1 into a Dewar vacuum flask with liquid nitrogen and seal off offtake 6. Perform this work wearing eye protection in the presence of your instructor ) After the pressure in the system becomes equal to 10 mmHg (in about 40-60 minutes), seal off offtake 8. Stop cooling test tube 1 and wait until the apparatus acquires room temperature. 

Phenylacetic acid. Into a 500-ml round-bottomed flask, provided with a reflux condenser, place 100 ml of water, 100 ml of concentrated sulphuric acid and 100 ml of glacial acetic arid add lOOg (98 ml, 0.85 mol) of benzyl cyanide. Heat under reflux for 45-60 minutes hydrolysis is then complete. Pour the mixture into 2-3 volumes of water with stirring. Filter the crude arid at the pump. Melt the crude material under water, and wash it two or three times with small volumes of hot water the acid solidifies on cooling. Test a small portion for the presence of phenylacetamide (m.p. 155 °C) by dissolving in sodium carbonate solution. If a clear solution results, phenylacetamide is absent if the solution is not clear, shake the whole of the crude product with excess of sodium carbonate solution, filter and precipitate the phenylacetic arid from the clear filtrate by the addition of dilute sulphuric arid. Filter off the phenylacetic acid and recrystallise it from hot water or, better, light petroleum (b.p. 40-60 °C). The yield of pure acid, 77 °C, is 50 g (43%). Small quantities of acid may be recovered from the mother-liquors by extraction with ether, but this is rarely worth while. Alternatively the acid may be purified by distillation under reduced pressure, b.p. 140-150 °C/20mmHg. The p.m.r. spectrum should be recorded and compared with that shown in Fig. 3.47. The 13C-n.m.r. spectrum is shown in Fig. 3.55. 

Some users specify a step cooling test of 21/4Cr-1 Mo. Step cooling simulates about half the increase in the ductile-brittle transition that will occur after a long-term service. A typical step cooling sequence is as... 

Bromide, (a) If iodide is present, this must be removed by treating one-third of the solution with 5 ml dilute H2S04 and 1 ml of 50 per cent KN02 solution (chloride-free). Boil the solution with stirring, concentrate to 3 ml and allow to cool. Test for bromide as under (Z>). 

Since a pulsed RF source is used for sparking rather than a continuous arc, the electrodes remain relatively cool. Tests have shown that the concentration of even volatile elements (e.g., mercury) is unaflEected by the sparking. Furthermore, the radiofrequency interruptions (ca. 

Introduce 20.0 g of cyclohexanol (technical grade), 5 mL of 85% phosphoric acid, and a boiling stone into a 100-mL round-bottomed flask and shake to mix the layers. Note the evolution of heat. Use the arrangement for fractional distillation shown in Fig. 6 in Chapter 5 but modified by use of a bent adapter delivering into an ice-cooled test tube in a 125-mL Erlenmeyer receiver, as shown in Fig. 11.1. 

I) 20 g of flowers of sulfur are suspended in 50 g of CS2 in a beaker, and the mixture heated to its boiling point. It is then poured rapidly through a fluted filter paper into a well-cooled test tube. Yellow crystals of orthorhombic sulfur are formed at once (colored figure 36). The residue in the filter paper can be used for further experiments. 

During the first eight days after cooling, tests were carried out, and showed that the molecular state underwent no change in air during this period, when rate of cooling (i), as above defined, had been employed. 

Following pilot experiments to determine the q>propriate sample size for statistical comparisons, seven specimens were analysed for the as-received condition of each product/colour combination. Each test specimen consisted of two links with a connector, cut from the same spool to avoid any effect of different batches. For the clinical testing, seven specimens of each product/colour combination were randomly placed in the mouths of the patients. The DSC analyses were performed from approximately -60 to 150 using a heating rate of 10 °C per minute. Dry ice was employed to cool test specimens to the starting temperature, and nitrogen was the purge gas. 

Construction continues on the HTR-10 at the INET site outside of Beijing, China. This pebble-bed helium cooled test reactor is being supported by the government of China. The construction permit for this plant was issued by the national safety authority at the end of 1994... 

The HTTR is a high temperature gas cooled test reactor which has various aims and operational modes. The construction of the HTTR has progressed smoothly and its first criticality is foreseen in December 1997. 

As mentioned above, NNSA had organized to establish technical documents before the licensing procedure started. The second document, namely the Standard Content and Format of the Safety Analysis Report of the lOMW High Temperature Gas-cooled Test Reactor, which defines the content framework of the Preliminary Safety Analysis Report of the lOMW High Temperature Gas-cooled Test Reactor (PSARy, has guided the compilation of the document. 

Before the licensing procedure started, the applicant had got the HTR-10 project approval from the State Education Commission and the approval of the Feasibility Study Report of HTR-10 from the State Science and Technology Commission. The Environmental Impact Report of the lOMW High Temperature Gas-cooled Test Reactor had been approved by the State Environmental Protection Administration. 

Institute of Nuclear Energy Technology, Tsinghua University Design Criteria for the lOMW High Temperature Gas-cooled Test Reactor, 1993... 

Reactions with dilvite sulfuric acid are similar. The reaction of copper with concentrated sulfuric acid can be demonstrated by the teacher in a fume cupboard. Goggles and chemical resistant gloves must be worn. Heat 1 g of copper turnings with 1 cm sulfuric acid - sulfur dioxide will be evolved. To dispose of the mixture, place cooled test tubes into a bowl of cold water. 

He should know the number of rods, crossheaders, tubes and cooled test holes and be able to discuss int iM.igently any unusual or experimental on-reactor facilities. Design features with safety implications should be well understood e.g., front face check valves, cap detents, scram drive systems, coolant backup, etc. 

Westinghouse Energy Systems conducts the passive containment cooling test analysis program. 

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